Shoe Containing A Progressive Compression Element

ABSTRACT

A cushioning component for use in shoes including athletic shoes and, for example, running shoes includes a cushioning layer including a first zone and a second zone where the first zone comprises a progressive compression material. 
     In one aspect, the first zone can comprise one or more areas defined within the second zone. For example, the first zone can comprise two areas, one area in a relative front portion of the shoe component and another area in a relative rear portion of the shoe component. 
     Alternatively, in another aspect, the first zone and second zone can be arranged in a laminate-type relationship in the shoe component. In this regard, the first zone can be located either above or below the second zone. 
     The shoe component can be employed as a traditional element of a shoe, such as a midsole or the outsole. Alternatively, the shoe component can comprise an additional component, for example, the shoe component can be employed between the midsole and outsole of a shoe or an insert located above the midsole.

This application claims priority under 35 USC 119 from provisional U.S. Application Ser. No. 60/855,687, entitled “Shoe Containing a Progressive Compression Element” by Steven E. Rosen, filed Oct. 30, 2006, which is incorporated by reference in its entirety for all purposes.

BACKGROUND OF THE INVENTION

In 2004, nearly 500 million pairs of athletic shoes were sold in the U.S.

There have been a number of studies looking at the impact of shoes on injuries in runners. See, for example:

-   -   http://www.physsportmed.com/issues/2005/0105/asplund.htm     -   http://www.cbssportsstore.com/sm-running-shoe-buyers-guide--bg-222919.html

The present invention relates to shoes and, in particular, to shoes having a cushioned sole.

One type of shoe associated with this invention is an athletic shoe, and in particular, a running shoe.

BRIEF SUMMARY OF THE INVENTION

Among other aspects, the invention relates to a cushioning component for use in shoes including athletic shoes and, for example, running shoes.

In one embodiment, the invention relates to a shoe component comprising a cushioning layer, which layer comprises a first zone and a second zone where the first zone comprises a progressive compression material.

In one embodiment of the invention, the first zone can comprise one or more areas defined within the second zone. For example, the first zone can comprise two areas, one area in a relative front portion of the shoe component and another area in a relative rear portion of the shoe component.

Alternatively, in another example, the first zone and second zone can be arranged in a laminate-type relationship in the shoe component. In this regard, the first zone can be located either above or below the second zone.

The shoe component according to the invention can comprise a traditional element of a shoe, such as a midsole or the outsole. Alternatively, the shoe component can comprise an additional component, for example, the shoe component can be employed between the midsole and outsole of a shoe or an insert located above the midsole.

In another embodiment, the invention relates to a shoe having a cushioning midsole comprising cushioning material including, but not limited to a cushioning polymeric material or a cellular material.

In another embodiment, the invention relates to a shoe having a cushioning outsole comprising:

-   -   a. a first upper zone comprising a cushioning material         including, but not limited to, a cushioning polymeric material         or a cellular material; and     -   b. a second lower zone comprising a resilient material.

In still another embodiment, the invention relates to a shoe having a cushioning sole system comprising:

-   -   a. a first upper zone comprising a progressive compression         material including, but not limited to a cushioning polymeric         material or a cellular material; and     -   b. a second lower zone comprising a solid rubber material.

In yet another embodiment, the invention relates to an element of a shoe that is capable of providing for an increase in the progressive compression of the shoe when worn, which element comprises a progressive compression providing material.

BRIEF SUMMARY OF THE DRAWINGS

FIGS. 1-3 illustrate examples of shoes according to the present invention.

DETAILED DESCRIPTION

As discussed above, the cushioning component of the invention includes at least one layer and having at least two zones—hereafter identified as a first zone and a second zone. However, it should be recognized that additional layers and/or additional zones could be employed within the context of this invention.

The cushioning component can be designed to be employed in connection with any shoe where the wearer desires to have a desired cushioning effect. Suitable shoes include any and all types of athletic shoes. Since the cushioning effect can be particularly useful in walking and jogging environment, running shoes are particularly suitable for use with the cushioning component of the invention.

One feature of the cushioning attachments of this invention is a first zone including a progressive compression material.

The term “progressive compression” in the context of this invention relates to those materials capable of providing a decreased rate of force application to one or more joints of the wearer by compression of the first zone progressively over the course of a step, e.g., a running step, i.e., the planting of the foot in stride, the rolling of the foot as the opposite foot swings forward and the lifting of the foot at the completion of the running step, as opposed to the rate that the force is applied in the absence of the device.

However, it is also preferred that the desired cushioning material is not overly soft as overly soft materials can (i) cause instability, increasing the risk of loss-of-balance as well as adverse effects on overall body posture during use and/or (ii) negate all or part of the progressive compression effect by collapsing too quickly thus transferring force more rapidly to the joints of the wearer.

In an example of a suitable material, the first zone can comprise a cushioning polymeric material. By “cushioning polymeric material” it is meant a material comprising at least one polymer, which polymer is in its viscoelastic, or rubbery, state between the temperatures of 10 F and 120 F, preferably at ambient temperature.

The cushioning polymeric material can comprises copolymers such as block copolymers and random copolymers, modified polymers or even blends of two or more polymers.

In one exemplary embodiment of the invention, the cushioning polymeric material includes those polymers which have been blow into a closed-cell cellular material.

Specific examples of suitable cushioning polymeric materials include one or more of foamed ethylene vinyl acetate, foamed polyurethane, foamed polyvinylchloride-polyacrylonitrile copolymer or foamed elastomeric polypropylene. One example of a suitable commercially available material is sold under the trademark of

Duralon®.

The invention also includes the use of first zones which comprise cellular materials. The cellular material can be either an open-cell cellular material or a closed cell cellular materials, in many instances, closed cell materials can be preferred.

The cellular material can be any cellular material recognized in the art, with cellular foam materials being a specific example of a suitable cellular material.

Specific examples of suitable cellular material include polyethylenes, polyvinyl chlorides, polychloroprenes, nitrites, nitrile-butadienes, urethanes, latex materials, and mixtures thereof.

Other examples of suitable cellular materials include polyethylene-vinyl acetate materials, polyvinyl chloride-nitrile materials, vinyl-nitrile materials, and nitrile-butadiene materials

In addition, the cellular material can comprise a rubber material. Suitable rubbers can include both natural and man-made rubbers. Specific examples of suitable rubber include, but are not limited to neoprene rubbers, nitrile rubbers, natural rubbers, styrene-butadiene rubbers, and ethylene propylene-diene rubbers.

In certain embodiments of the invention, suitable materials for use in connection with the first zone include those materials having an elastic modulus (compressibility), which is measured in megapascals (MPa) that is not greater than 1 MPa. In other embodiments, the first zone comprises materials having an elastic modulus not greater than 0.9 MPa, or even no greater than 0.8 MP.

In addition, the first zone can comprise materials having an elastic modulus not less than 0.6 MPa, and even, not less than 0.5 MPa or, even still not less than 0.4 MPa.

The invention also envisions the use of first zones which comprise materials having a compression deflection of not greater than 0.7 according to ASTM D575. Moreover, in certain embodiments of the invention, the use of materials having a compression deflection of not greater than 0.5 according to ASTM D575 can be employed.

In addition, the first zone can employ those materials having a compression deflection of not less than 0.2 according to ASTM D575. Moreover, the use of materials having a compression deflection of not less than 0.1 according to ASTM D575 can be employed.

The compression deflection of suitable materials employed in the first zone can also be characterized according to ASTM D1056. In this regard, the use of materials having a compression deflection of not greater than 30 psi according to ASTM D1056 can be employed. In other embodiments, the use of materials having a compression deflection of not greater than 20 psi according to ASTM D1056 can be employed. In still other embodiments, the use of materials having a compression deflection of not greater than 17 psi according to ASTM D1056 can be employed.

The invention also includes embodiments wherein the material for the first zone has a compression deflection of not less than 9 psi according to ASTM D1056. In addition, the attachment of the invention includes embodiments where the material for the first zone has a compression deflection of not less than 6 psi according to ASTM D1056. Still other embodiments employ materials having a compression deflection of not less than 4 psi according to ASTM D1056.

In addition, additives such as internal lubricants (or plasticizers) and mineral fillers can be introduced into the polymer in order to modify or improve one or more property of the polymer. Specific examples of suitable additives include carbon and silica fillers.

Additional suitable materials for use in connection with the first zone include those materials previously employed in an “anti-fatigue” environment, e.g., anti-fatigue pads, mats, runners and the like. In this regard, anti-fatigue mats are designed to make workers more comfortable when they must stand on their feet for many consecutive hours. Anti-fatigue mats offer more cushioning not only for comfort but also to improve circulation and absorb shock, helping to reduce muscle tension, aches, and general fatigue.

Suitable materials include those rubber materials-both natural and man-made-materials employed in connection with anti-fatigue mats and the like. Examples of such materials include natural rubbers, nitrile rubbers and modified nitrile rubbers which are recognized in the art. Specific examples of suitable anti-fatigue materials are sold under the Nitricell® trade name from the Wearwell Company.

A specific example of a suitable material for use in the first zone is Ensolite® available from Armacell LLC. Ensolite is a PVC/NPR polymer having the following characteristics:

25% Compression Resistance (psi), ASTM D-1056, 5.0 to 8.0

50% Compression Set (%), ASTM D-1056, 25 max.

Density (lb/ft.3), ASTM D-1056, 6.5 to 8.5

Water Absorption (lb/ft2), ASTM D-1667, 0.1 max.

Tensile (psi), ASTM D-412, 80 min.

Elongation (%), ASTM D-412, 100 min.

C-Tear Strength (lbs/in.) ASTM D-624 Die C 10 min.

Temperature Use: ASTM D-1056 Cold Crack −20 C and High 200 C

A second consideration in connection with the first zone is the thickness of the progressive compression material.

The thickness is capable of affecting the cushioning ability of the attachment. As such, the preferred thickness can be dependent upon a number of factors including the nature of the cushioning component, (e.g., as a midsole, an outsole or a additional element of the shoe), material of construction, the type of shoe to which the component is to be employed, the desired function of the shoe for the wearer, the shape, height and weight of the wearer of the shoe/attachment combination and even the environment and weather conditions that the wearer is likely to face.

For example, a 300 lb man may prefer the use of an attachment with a thicker first zone than a 100 lb woman. Similarly, a runner who is running on harder surfaces may prefer a different thickness than one who is running on relatively softer surfaces.

Optimization of the thickness for any particular material of construction would be within the purview of those skilled in the art. For example, where the component is an outsole of the shoe, in optimizing the thickness of the first zone, one should also consider the concept of bottoming out, i.e. the bottoming out point for the material in question, and the “densification strain” (bottoming out point as a percentage of thickness). The invention envisions the use of densification strains greater than 40%, greater than 50% and even greater than 60%, still even greater than 70% or 80%.

As was the case with the thickness of the first zone, the nature of the second zone can be largely dependent on the overall purpose and/or location of the cushioning component layer in the shoe.

For example, where the cushioning component is to be employed as the midsole of a shoe, the second zone can comprise materials which are suitable for use in traditional midsole construction.

The construction of midsoles for shoes is very well recognized in the art. For example, attention is directed to the following websites which illustrates key features in midsole construction:

-   -   http://www.scire.com/sds/Pages/partmid.html     -   http://www.americanrunning.org/displayindustryarticle.cfm?articlenbr=1430     -   http://www.coolrunning.com/engine/2/running-shoe-guide-for-du-2.shtml

As can be seen, the use of a variety of additional cushioning elements, from foams to air pockets to liquid pockets has been employed in the construction of midsoles. As such, they can be effectively employed in connection with the second zone of the invention.

Moreover, the relationship of the first zone to the second zone can be widely varied. For example, the first zone can be defined in one or more areas of the midsole, surrounded by the second zone. Such an arrangement is illustrated in FIG. 1. The number of first zone areas is dependent on a number of factors including the nature and purpose of the shoe and optimization of such is within the purview of those skilled in the art.

Alternatively, the first zone and the second zone can be arranged or ‘layered’ in a laminate-style arrangement such as that shown in FIG. 2. Once again, the second zone can comprise one or more layers depending on the nature and purpose of the resulting shoe.

In each case, the material of construction of the second zone can be selected to optimize the properties of the cushioning component—in this case, the midsole of the shoe.

In another alternative, the cushioning component can be employed as an outsole for a shoe. In fact, as was the case with the midsole, the construction of outsoles is well-recognized in the art. See, for example, the following website:

-   -   http://www.scire.com/sds/Pages/partout.html

In one example of this aspect of the invention, the component can have a laminate-type arrangement in which where the first zone is typically be a layer located above the second zone.

Functions of the second zone in such an arrangement typically include one or more of (i) providing for a more resilient surface, e.g., sole, in contact with the ground, as compared to the first zone, and (ii) improving the traction of the shoe.

The material of construction for the second zone is not critical and can include any material capable of providing the desired function. Specific examples of suitable materials include resilient materials such as solid rubber materials.

Examples of suitable materials of the second zone in such constructions include any of those material recognized in the art for use in outsoles of shoes, and in particular, running shoes.

The thickness of the second zone is not critical to the invention as long as it does not adversely impact the desired function of the component as an outsole of a shoe or the cushioning function of the first zone.

In another embodiment of the invention, the cushioning component can comprise an additional component, such as an insert, for the shoe. As such the insert can include features of inserts that are recognized in the art. Such inserts are recognized in the art, see for example:

-   -   http://www.scire.com/sds/Pages/partinst.html

In another example of this aspect of the invention, the insert can comprise materials in order to enhance the function of the first zone. In one example of such an embodiment, the first zone can comprise a layer of progressive compression material while the second zone can comprise one or more reinforcement means attached to one or both sides of the first zone. Moreover, the second zone can comprise one or more layers of material, however, in most situations, a single layer is adequate.

The second zone can comprise any material that can be effectively attached to the material of the first zone and is preferably capable of improving the durability of the cushioning material. For example, the use of a reinforcement layer can improve the tensile or tear resistance of the first zone. Specific examples of suitable materials include fabric materials such as nylon, Dacron, polyester, cotton, or mixtures thereof.

The reinforcement layer(s) of the second zone can be attached to the cellular material by way of any technique recognized in the art of Suitable techniques include the use of adhesive materials such as polyurethane, acrylic, epoxy, and cyanoacrylate adhesives that are recognized in the art.

In yet another embodiment, the cushioning component can comprise a layer that is employed between the midsole and the outsole of the shoe. In such an arrangement, the structure of the component can be similar to that of the insert discussed above. Alternatively, the structure of the component can be similar to that of the midsole as discussed above. As was discussed above, optimization of the structure to provide for enhanced progressive compression is within the purview of those skilled in the art.

FIGS. 1-3 illustrate examples of shoes employing cushioning component of this invention.

FIGS. 1 a-b illustrate a shoe 1 wherein the outsole 2 has a first zone of progressive compression material present in two areas 3 in the second zone 4.

FIGS. 2 a-b illustrate a shoe 11 where the outsole 12 has a first zone of progressive compression material 13 defined in a laminate relationship with the second zone 14. FIG. 2 b illustrates a cross section which further shows midsole 15.

FIGS. 3 a-b illustrate the cross-section similar to that of FIG. 2 b. FIGS. 3 a and 3 b illustrate two alternative examples of shoes according to the invention.

In FIG. 3 a, the shoe 31 includes outsole 32, midsole 35 and insole 36. In FIG. 3 a, the cushioning layer is the midsole 35 of the shoe. In FIG. 3 b, the cushioning layer 37 is between the midsole 35 and the insole 37. 

1. A shoe component comprising a cushioning layer, which layer comprises a first zone and a second zone where the first zone comprises a progressive compression material.
 2. The shoe component according to claim 1 wherein the first zone comprises one or more areas defined within the second zone.
 3. The shoe component according to claim 2 wherein the first zone comprises at least two areas including at least one area in a front portion of the shoe component and at least one area in a rear portion of the shoe component.
 4. The shoe component according to claim 1 wherein the first zone and second zone are arranged in a laminate-type relationship in the shoe component.
 5. The shoe component according to claim 4 wherein the first zone is located above the second zone.
 6. The shoe component according to the claim 1 wherein the component is the midsole of a shoe.
 7. The shoe component according to claim 1 wherein the component is the outsole of a shoe.
 8. The shoe component according to claim 1 wherein the shoe component is employed between the midsole and outsole of a shoe.
 9. The shoe component according to claim 1 wherein the shoe component is employed above the midsole of a shoe.
 10. The shoe component according to claim 1 wherein the component is employed in an athletic shoe.
 11. The shoe component according to claim 1 wherein the component is employed in a running shoe.
 12. The shoe component according to claim 1 wherein the progressive compression material comprises a cellular material.
 13. The shoe component according to claim 12, wherein the cellular material comprises a closed cell material.
 14. The shoe component according to claim 12 wherein the cellular material comprises an open-cell material.
 15. The shoe component according to claim 12 wherein the cellular material comprises a foam material.
 16. The shoe component according to claim 12 wherein the cellular material comprises a polyethylene, a polyvinyl chloride, a polychloroprene, a nitrile, a nitrile-butadiene a urethane, a latex, and mixtures thereof.
 17. The shoe component according to claim 12 wherein the cellular material comprises a polyethylene-vinyl acetate material, a polyvinyl chloride-nitrile material, a vinyl-nitrile material, or a nitrile-butadiene material.
 18. The shoe component according to claim 12 wherein the cellular material comprises a rubber.
 19. The shoe component according to claim 18 wherein the rubber comprises a neoprene rubber, a nitrile rubber, a natural rubber, a styrene-butadiene rubber, or an ethylene propylene-diene rubber.
 20. The shoe component according to claim 1 wherein the progressive compression material is a cushioning material.
 21. The shoe component according to claim 20 wherein the cushioning material comprises at least one polymer, which is in its viscoelastic state between the temperatures of 10 F and 120 F, and which has been blown into a closed-cell cellular material.
 22. The shoe component according to claim 20 wherein the cushioning material comprises a modified polymer or a blend of two or polymers.
 23. The shoe component according to claim 20 wherein the cushioning material comprises one or more of foamed ethylene vinyl acetate, foamed polyurethane, foamed polyvinylchloride-polyacrylonitrile copolymer, foamed elastomeric polypropylene or Duralon®.
 24. The shoe component according to claim 1 wherein the second zone includes one or more additional cushioning elements.
 25. A shoe comprising an insole, midsole and outsole, wherein at least one portion of the shoe includes a cushioning layer, which layer comprises a first zone and a second zone where the first zone comprises a progressive compression material. 